Blocked drains — causes and what a plumber checks
Slow-draining sinks are usually a local blockage (grease, hair, food waste) that a plumber can often clear with rodding or a drain snake. A blockage affecting multiple fixtures at once, or gurgling sounds from other drains, points to something further down the system — sometimes needing a drain camera survey rather than guesswork.
Outside taps and garden plumbing
An outside tap needs its own isolation valve and, in colder areas, either an internal shut-off you can drain down for winter or a proper anti-frost design — a poorly installed one is a common cause of a burst pipe in cold weather. This is separate from the electrical requirements for any pond or irrigation pump also being installed.
When plumbing work needs a Gas Safe engineer instead
Plumbers can install and repair most water systems, but any work on a gas appliance or gas pipework — a boiler, a gas fire, a gas hob — is illegal for anyone who isn't on the Gas Safe Register, by law. If a job involves both plumbing and a gas connection (moving a boiler, for example), check whether your plumber is also Gas Safe registered before booking.
Three steps to hiring the right plumber
First, check they're registered with a WaterSafe scheme (or Gas Safe too, if the job needs it) and ask for the registration number. Second, get a written quote that separates labour from parts. Third, ask what happens if the job uncovers a bigger problem — a good plumber will tell you before continuing, not after.
How plumbing quotes work
Describe the job, including whether it's an emergency, a planned repair, or a full installation, and mention access — under a suspended floor is very different from behind fitted units. Plumbers use this for an initial estimate; the final price is usually confirmed once they've seen the fault or the space in person.
Hard water and your plumbing
In hard water areas, limescale builds up inside pipes, taps, showerheads and boiler heat exchangers over time, gradually reducing efficiency and flow. A plumber working in a hard water area may recommend a water softener or scale inhibitor as part of a boiler installation, particularly for a system that's expected to last 10+ years.
What is a power flush and do you need one?
A power flush clears sludge and debris from a central heating system's radiators and pipework using a pumped chemical flush — usually recommended if radiators are cold at the bottom, or before installing a new boiler onto an older system, so the new boiler isn't immediately clogged by old sludge.
Heat pumps and eco-friendly heating options
Some plumbers also work on or alongside heat pump installations, though this is often a joint job with a heating engineer for the heat pump unit itself. If you're considering moving away from a gas boiler, it's worth asking whether your plumber does this work directly or partners with someone who does.